How many cycles per second does AC shore power in the US have?

How many cycles per second does AC shore power in the US have?

• A. 60
• B. 50
• C. 120
• D. 30

Answer: (A)

The main concept here is the frequency of alternating current, measured in hertz, which tells you how many times the waveform completes a full cycle each second. In the United States, standard shore power runs at 60 hertz, so the current completes 60 cycles every second. The other numbers refer to different properties: 50 hertz is the standard in many other parts of the world, not the US; 120 is a voltage value (typical US mains is about 120 V), not the cycle rate; 30 hertz isn’t used as the standard for US shore power.

The main concept here is the frequency of alternating current, measured in hertz, which tells you how many times the waveform completes a full cycle each second. In the United States, standard shore power runs at 60 hertz, so the current completes 60 cycles every second. The other numbers refer to different properties: 50 hertz is the standard in many other parts of the world, not the US; 120 is a voltage value (typical US mains is about 120 V), not the cycle rate; 30 hertz isn’t used as the standard for US shore power.